Telephone networks of various kinds are known in the prior art. Similarly known are Community Antenna Television (CATV) video distribution systems of various kinds.
Some commentaries speculate that digital systems will provide 500 channels of video information into each subscriber's home in the near future. The trend in development work on video distribution, as in many communication industries, is toward all digital transmissions. In particular, a number of systems have recently been proposed for distributing video information in compressed, digital data form.
The prior art, however, is limited in the degree to which telephone and video distribution have been integrated. Other digital services generally operate over specialized networks. There is a need for a full service network which can accommodate a full range of digital services.
U.S. Pat. No. 5,247,347 to Litteral et al., assigned in common with the present invention and herein incorporated in its entirety by reference, integrates a public switched telephone network with video-on-demand service. The video-on-demand system shown in this patent adopts existing components of the Public Switched Telephone Network (PSTN) and implements compression techniques to store video information for subsequent forwarding over interoffice facilities. The switching facilities are located in central offices (COs) serving residential customers or subscribers. Electronic devices associated with the subscriber loops modify the transmission characteristics of the subscriber loops to permit delivery of full motion video information over existing loop plant facilities. The Litteral patent discloses the use of Asymmetric Digital Subscriber Line (ADSL) interface units for providing video-on-demand to subscribers from the central office.
U.S. patent application Ser. No. 08/233,579, in the name of Bruce Kostreski, filed Apr. 26, 1994, assigned to the common assignee and entitled Extended Range Video On Demand Distribution System (docket no. 680-074), the disclosure of which is herein incorporated in its entirety by reference, describes improvements in ADSL distribution of video to subscribers in which fiber optic links are used to connect video sources at a central office to remote intermediate distribution points from which ADSL links provide the connection to subscribers' premises.
The networks of the prior art typically have not been designed to accommodate a full range of digital services such as telephone, video, video-on-demand, data services, information services, interactive services, and other modern digital offerings.
Specifically, prior art networks typically have not been capable of the wide bandwidth required to deliver broadband services such as real time video to subscribers premises.
Further, prior art networks typically have not been capable of:
providing low routing delays needed for interactive type of services, PA1 handling video broadcast services to all subscribers, PA1 centrally managing video services, PA1 providing individualized video services at the request of the subscriber, or PA1 connecting video, wide band data, narrow band data, and telephone information in an integrated manner.